The invention relates to a torque-sensing clutch, arranged to transmit a torque between two shafts or other rotating components. The one shaft has a sleeve-shaped portion surrounding the other shaft and one of them has means which, in their activated state, engage recesses in the other clutch part. When the transmitted torque exceeds a predetermined limit value the positions of said means are changed whereby the clutch engagement is released.
Prior art shaft clutches of the type above referred to are described in e.g. CH A No. 541 739 and DE B No. 2 729 775. It is a common feature to both those prior art designs that the coupling means are constituted by rigid metal bodies, more specifically steel balls, which are in radially directed grooves displaceable between an activated position and a released position. They are retained in their activated positions by an elastic force generated by pressure springs which act directly or via hydraulic plungers. Consequently, such clutches are relatively complicated from a structural point of view. They also suffer from the functional limitation that the value of the transmitted torque at which this engagement occurs is fixed and cannot conveniently by changed.